Proposal:Tag:service=bus bay

Tag:service=bus_bay
Proposal status:	Draft (under way)
Proposed by:	ManuelB701
Tagging:	service=bus_bay
Applies to:
Definition:	Mark ways solely to access bus platforms (including bus bays).
Statistics:
Draft started:	2024-08-14

The bus stop Sankt Bernhard (eastward) in Mainz. Unlike most bus stops, this one is separated by a traffic island from the rest of the street.

Proposal

The purpose of this proposal is to formally add a definition for service ways which for bus bay which are separate from the carriageway and by extension, any way whose purpose is to access bus platforms. It also includes a better definition to unify the curring tagging practices.

It also includes some synonyms which should be depreacted in favour of standardisation.

Rationale

Currently, bus bays are tagged using bus_bay=* which works for bus bays which are segregated at most — if at all — by kerbs from the main carriageway and appear like street side parking spaces (to the point where they're sometimes reporposed from one), the tagging fails a stronger barrier between the bus bay and a carriageway is used. In that case, the bus bay is its own way and the platform has to be accessed from that way but the current tagging can't reflect this.

The problem right now is that there are different mapping standards to tag bus bays. The following practices have been in use:

• Bare highway=service: An established tag, used for any way whose main purpose isn't transit (i.e. throughfare) and the de jure way of mapping bus bay ways. Generally sufficient the same way parking aisles and driveways can be tagged without service=*.
• Bare highway=busway: A relatively new tag which is used to denote bus-only ways / protected bus lanes, especially because they're commonly used for bus bay ways where protected bus lanes are uncommon. Potential misuse because bus bays are not lanes and doesn't fit the busway definition much like how bus bays aren't lanes.
• highway=service with service=driveway: Use of the tag is intended to access properties. Potential misuse because bus bay ways don't access properties but also generally lead to dead ends while bus bays continue onwards.
• highway=service with service=parking aisle: Use of a tag is intended to serve access for parking spaces and a bus bay is seen as a type of parking. Potential misuse because the intention is for ways within a parking lot, for ways between parking spaces, but not to the parking lot itself.
• highway=service with service=drive-through: Use of tag is intended to access a service (like a shop) from a car. The most fitting option (in that the "service" is a bus platform) but still a potential misuse because there is no shop to access.

Quality assurance like PTNA will complaining about the latter three tags for how unusual they are for busses and how they're unsuited for them.

service=bus_bay covers another relatively common use of service roads while also standardising the tagging practices. As of now, it's been used seven times (including four times by me). Some alternative tags also have been used for similar purposes:

• service=busservice (as of now only used for bus bays)
• service=Bus (used both as busways and bus bay ways, possibly a synonym to highway=busway)
• service=busbay (alternative spelling of the proposed tag, inconsistent with current bus_bay=* tag)

Why not on highway=busway?

The rationale is that busways are essentially bus lanes as separate ways among some other definitions but bus bays by definition are not lanes (nor do they count as proper lanes). For bus bay ways, their main function isn't transit but rather serve an access to bus stops which is consistent of the definition of highway=service. This is particularly notable if express busses exist which never enter the bus bay because they don't serve the stop.

Furthermore, bus bays are to roadways what passing loops (with stops) are for railways and the latter are tagged as service=siding which classifies them as service tracks. The analogy for highways is therefore to treat bus bay ways as service roads and not busways.

One thing what both have in common is that they primarily if not only serve busses and use similar signs (e.g. a blue circle with a white bus under the Vienna Convention).

Why not bus_bay=yes?

The intend of bus_bay=* is to denote whether a highway has' a bus bay but not whether a way is a bus bay. In other words, bus_bay=yes has the implication that some bus bay exists along the given highway (albeit without the specification on where it exists exactly) and thus implies the bus bay way has its own bus bay. service=bus_bay lacks this ambiguity. This is similar to the mapping of sidewalks where instead of using sidewalk=yes on footways (which implies there is a sidewalk to the sidewalk), one is using footway=sidewalk instead.

Tagging

General tagging

Draw a highway=service way and add service=bus_bay to it. Due to their nature, most bus bays ways (such as next to to kerbs) also are oneway but exceptions do exist (particularly if the bus bay is in the highway median). The tag implies bus=designated but general access per-se might not be forbidden.

For the way the bus bay is branching off, either leave it without a bus_bay=* (or tag the other side having one if that's the case) or use at most a bus_bay:side=separate (akin to separately mapped cycletracks). Never use bus_bay=side because that implies a second bus bay alongside a separate one nor should the bus bay way be tagged as such.

When to use service=bus_bay

• The most simple case: The bus bay is separated by a barrier e.g. there is a traffic island separating it from the main highway.
• A short, parallel way to a main highway solely to access bus platforms (the difference to the above is that these ways are bi-directional but it also results in some busses crossing with general traffic when they enter this side way).
• General access to bus platforms (this happens if the platform is located inside a loop off from a highway)
• Ways inside bus terminals and potential access to them. This is the most similar to service=parking aisle but also slightly broader in scope as it may also be used to access the bus terminal. Main transit and general service ways still should be tagged appropriately, though.

When not to use service=bus_bay

• No clear entrance and exit in which case no way should be drawn at all:
  • The bus bay is merely a carriageway extension with no (non-paint / -surface) separation. You don't draw extra ways for a new lane.
  • Drawing a way into a bus bay whose separation is at most a continuous kerb. Drawing a separate way here also is verboten because no singular way can be drawn (akin to how one doesn't draw a way for street side parking parking but certainly for parking lots). The distinction is more useful when tools exist to map bus bay areas, though.
• They are not an alternative to highway=busway.
  • That means, protected bus lanes still should be tagged with highway=busway.
  • If the supposed "bus bay" actually extends for quite a while (e.g. up to the next stop), it's a proper busway (akin to the distinction between long passing loops and proper multi-tracks for railways).
• Short bus-only streets also are excluded in the definition.
• If the service road doesn't provide access to a bus stop but (also) for other purposes, the service road is not for a bus bay.
• Transit malls and other bus-only streets, no matter how short, don't classify as bus bays either.

Edge cases

There still are cases where it's ambiguous on whether to use service=bus_bay or any other tug such as highway=busway. The purpose of this proposal is to clarify these edge cases before the tag will be used in practice.

(This is one where one should discuss throughout by bringing up pro and contra arguments and might include other cases. Once they've been settled, they'll be included in the respective sections. Voting will start once they've been properly defined.)

A painted bus lane approaches a platform

Interpretation for highway=busway:

• The way is an extension of a bus lane which now is physically seperated
• Even busses which skip the stop still pass by the platform

Interpretation for service=bus_bay:

• The only reason the ways are separate from the carriageways is because of the platform which makes them bus bays by default.
• The short way isn't long enough to be classified as highway=busway

Examples

• This way is a classic example of a protected bus bay: It's separate from the main carriageway by a traffic island
• Here, the platform is located on the median of the road but the approach is the same: It allows busses to access the (tram) platform but doesn't allow to drive with trams (these ways naturally should include embedded rails=tram.
• That one is a parallel way example: The way is bus-only and only exist to serve platforms B and C. Any other vehicle has to drive on the main highway and moreover, none of the busses which don't stop at these platforms don't enter this way either (as seen by this relation.

Features/Pages affected

• service=bus_bay: Create page
• bus_bay=*: Add link to service=bus_bay
• highway=busway: Add link to service=bus_bay

Comments

Please comment on the discussion page or the corresponding thread in the forums.